EVLA Memo 109 Wideband Performance of the EVLA L-Band System
نویسنده
چکیده
The performance of the EVLA L-band feed/receiver across its full 1.0 – 2.0 GHz range is presented. The median efficiency across the band is near 45%, rising by about 4% near 1300 MHz and 2000 MHz, and dropping by a similar value near 1600 MHz. The efficiency drops quickly below 1100 MHz. The variation of focus position with frequency follows predicted values, and an optimum position for wide-band observations causes less than 2% loss in efficiency at any frequency. The increase in system temperature with decreasing elevation is nearly independent of frequency.
منابع مشابه
EVLA Memo #152 Characterizing the Sensitivity of the EVLA at L-band
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